K for individual plastic face panels of internally illuminated sign box

ABSTRACT

A CHANNEL SEAM LOCK FOR REMOVABLY SECURING TOGETHER PANELS OF AN INTERNALLY ILLUMINATED SIGN BOX OR THE LIKE.

Inventor Filed Patented Apr. 13, I971 SEAM LOCK FOR INDIVIDUAL PLASTICFACE PANELS OF INTERNALLY ILLUMINATED SIGN BOX AttomeyShoemaker andMattai e 12 Claims, 3 Drawing Figs.

U.S. Cl 350/319, 40/125, 52/584 Int. Cl G02b 5/00, G021: 27/00, EO4c1/30 Field of Search 350/319;

Jerome Rosenberg [56] References Cited 11 Siaulies Drive. Plainview, NY.11803 UNITED STATES PATENTS 820 123 1,718,014 6/1929 Westhn 2,806,3089/1957 Curell 3,002,591 10/1961 Hess 3,352,073 11/1967 Hippie 52/584;40/125 (F), (HK); 267/(lnquired);

l60/(lnquired); 40/125 Primary Examiner-David Schonberg AssistantExaminer-T. H. Kusmer ABSTRACT: A channel seam lock for removablysecuring together panels of an internally illuminated sign box or thelike. I I

SEAM LOCK FOR INDIVIDUAL PLASTIC FACE PANELS OF INTERNALLY ILLUMINATEDSIGN BOX BACKGROUND OF THE INVENTION This invention relates to devicesfor holding together the panels of internally illuminated sign boxes. Itis not unusual for these sign boxes to be 40 feet long or more and dueto the limited size of the panels used in the face of the signs, it isnecessary to use a plurality of transparent or translucent panels heldin edge abutting relationship in order to make up a complete face forthe sign. This means that in these signs there will be at least twopanels making up the face of the sign and at least one seam across theface of the sign where the panels abut. Various methods have been usedin the past to secure these panels in place, but they have not provensatisfactory for one reason or another. One such method, for example,was to place two panels in edge abutting relationship and then cement orotherwise fix a strip or plate of reinforcing material along thejuncture of the two panels thus covering the back of the seam andholding the panels in place. The resulting structure was unsatisfactorybecause the rigid seam did not compensate for contraction and expansionof the panels due to changes in ambient temperature, it being necessaryto provide for such contraction and expansion at the outer edges of thecomplete face of the sign, which caused cracking and breaking of therigidly held panels. As aconsequence of the resulting strain on therigid seam, they frequently failed, enabling wind, rain etc. to enterthe seam and bulge the sign face outwardly, destroying the sign. Also,if one panel was damaged, it was generally necessary to replace theentire face of the sign since the panels could not be readily separated.This same disadvantage necessitated removal of the entire sign face fornormal periodic service and maintenance. Further, the flat platecemented across the back of the seam caused light refraction resultingin localized shadows and discoloration on the sign face.

OBJECTS OF THE INVENTION It is an object of this invention to overcomethese disadvantages and provide a new and unobvious structure for' foran internally illuminated sign box wherein the seam lock does not causeshadows or discoloration on the panels constituting the face of the signbox.

It is still a further object of this invention to provide a seam lockfor an internally illuminated sign box wherein the edges of the adjacentpanels are movably held in spaced relation to compensate for contractionand expansion of the panels of the sign box due to changes in ambienttemperature.

It is also an object of this invention to provide a seam lock for thepanels of an internally illuminated sign box which comprisesprefabricated channels of extruded or molded plastic material.

An even further object of this invention is to provide a seam lock forthe panels of an internally illuminated sign box which is dependable andwhich is simple and economical to manufacture.

It is still a further object of this invention to provide a panel seamlock for internally illuminated signs which can be readily assembled ordisassembled in any position, such as flat on a horizontal surface orvertically in a sign.

Still another object of this invention is to provide a panel seam lock"for internally illuminated signs wherein the seam lock can be made inthe form of standard lengths that may be cut in lengths as needed.

Other objects and advantages of the invention will become apparent froma study of the following detailed description of the invention and ofthe drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a perspective of anassembled sign embodying the DETAILED DESCRIPTION OF THE DRAWINGS Apreferred embodiment of the invention is illustrated in FIGS. 1 through3 of the drawings wherein like reference numerals refer to like partsthroughout the several views.

Referring to FIG. 1, the present invention is shown embodied in a signcomprising a hollow housing I constructed in a well-known manner andhaving attaching or supporting legs 2 and 3 depending therefrom. Thesign face is made up of a plurality of flat transparent or translucentrectangular or of any other desirable shape plastic sheets or panels 4,4', 4", 4" which as shown are assembled in side-by-side relationship orany other suitable arrangement according to the present invention.

Referring now to FIGS. 2 and 3, the details of the panel seam lock ofthe present invention are seen. The panel seam lock of the presentinvention comprises, as shown, a pair of substantially identical plasticU-shaped channel members 5 and 5', each having a similar web 6, 6 withinner similar flanges 7, 7 extending outwardly at substantially rightangles to said web 6, 6, the opposite edge of said web, 6, 6' havingsubstantially similar outer right angularly extending flanges 8 and 8;the flanges 7 and 7 being of less width than the flanges 8, 8', saidflanges being substantially coextensivein length with their respectivewebs 6, 6. The outer faces of each outer flange 8, 8' of the channelmembers 5, 5' is secured by an adhesive or other suitable securing meansto adjacent marginal portions M, M of each panel 4, 4 and with the webs6, 6 substantially in back-to-back contact with each other. The outersurface of terminating bight portions of each inner and outer flange isin substantially in the plane of end edges of each panel. A plasticC-shaped locking channel member 10 or other suitable locking means iscomprised of an outer wall 11 of greater overall width than the combinedwidth of flanges 7, 7, thus providing spaces 7a and 7b allowing forexpansion of the seam, and with similar downwardly extending sidewallsl2 and 13 extending at right angles from opposite edges thereof, withinwardly directed flanges I4 and 15 extending at substantially rightangles from the sidewalls l2 and 13 and terminating short of each other,leaving a gap A between the side edges thereof. This gap A issubstantially twice the combined cross-sectional thickness b of the webs6, 6' of two adjacently placed U-shaped channel members 5, 5'. 7

When assembled, the flanges 7, 7' of U-shaped channel member 5, 5' onadjacent edges of the panel members 4, 4

are slidably received in recesses I6 and 17 of locking channel memberI0, thus releasably locking adjacent channel members 5, 5' and theirassociated panel members 4, 4' together. The tolerances or differencesin dimension permit the seam to move a restricted amount in theassembled device when the panels 4, 4' expand or contract due to ambienttemperature changes and thus relieve any stresses which might otherwiseoccur, but at the same time, the seam lock of the present inventionprovides a secure fastening means for safely holding together theplurality of panels used in a multiple panel sign face.

An important aspect of this invention is the selection of radii R, and Rat the juncture of flanges 8, 8'- with the webs 6,

- an outside radiusR of one-sixteenth inch.

The various elements. comprising the present invention may be selectedfrom any suitably rigid and transparent or translucent plastic materialor any other suitable material but the material as used in oneembodiment are clear acrylic for the U-shaped channel members 5, 5'white acrylic for the C- shaped locking channel member and plexiglas forthe panel members 4, 4'. The use of clear acrylic for the U-shapedchannel members 5, 5-. diminishes the possibility of light diffusion anddiscoloration in the panels 4, 4' comprising the sign face and the useof white acrylic for the C-shaped locking channel member serves to backup the opening between adjacent panel members 4, 4', thus providing acontinuous, unbroken white coloration in the sign face.

SUMMARY The seam lock for panels on an internally illuminated sign boxas defined by the present invention provides a new, useful and unobviousmeans-of releasably securing together the panels making up the face ofthe sign in a manner to enhance the esthetics of the sign, make the signeasy to service and repair, reduce discoloration and shadowing of thesign face, provide for expansion and contraction of the panels due toambient temperature changes, and practically eliminate danger of thepanels blowing ofi" due to wind and other elements entering the seams.

It should be understood that the specific preferred embodiment of theinvention as described herein is not intended to be limiting in anysense but that various modifications in structure and different uses ofthe inventive concepts involved are contemplated which come within thescope and incorporate the novel principles of the present invention. Forexample, the same inventive principles might be employed in hangingpaneling when decorating walls, or in applying decorative faces tobuildings, or in applying automobile trim etc.

It is intended that the present invention be limited only by the scopeof the appended claims and all reasonable equivalents in structure andfunction thereof.

lclaim:

l. A seam lock for releasably securingtogether adjacent panels arrangedin edge-to-edge relationship comprising, a first locking member securedalong adjacent marginal edges of each ofa pair of adjacent panels and asecond locking member releasably interfitted with said first lockingmembers to hold said first locking members and their associated adjacentpanels in assembled relationship, said second locking member includingrecess means therein, laterally projecting means on each of said firstlocking members received in said recess means, said recess means beinglarger than said laterally therethrough and constructed to minimizerefraction and diffusion of light passing through said panels in thevicinity of said locking means to preclude shadows and discoloration'andtranslucent material and comprises channel members havin preselectedcorner radii such as to minimize refraction an diffusion of lightpassing therethrough.

4. Seam lock for securing together a plurality of panels as defined inclaim 2 wherein said locking means comprises first locking means carriedby adjacent marginal edges of the panels and second locking meanssimultaneously interengaging and interlocking with said first lockingmeans to releasably hold the panels in said edge-to-edge relationship,said first locking means comprising a web portion and an outer flangeextending at substantially right angles from an edgeof said web portion,the outer surface of said flange being affixed to the back of a paneladjacent a marginal edge thereof with the webs of adjacent'locking meansextending substantially perpendicularly and in back-toback relationshipfrom the back of adjacent panels, said second locking meansinterengaging and interlocking with said web portions.

5. Seam lock for securing together a plurality of panels as defined inclaim 4 wherein said first locking means is generally U-shaped with aninner flange extending substantially perpendicularly from the oppositeedge of said web, said inner flange being interengaged and interlockedwith said second locking means.

6. Seam lock for securing together a plurality of panels as defined inclaim 5, wherein said second locking means comprises a generallyC-shaped locking channel member having an outerwall andtwo dependingsidewalls extending substantially perpendicularly from opposite edges ofsaid outer wall, each of said sidewalls having an inwardly directedflange means extending parallel to said outer wall and terminating shortof each other, defining inwardly facing recesses, each of said recessesslidably receiving an outer flange of two adjacent generally U-shapedlocking members thereby releasably holding said U-shaped locking membersin back-to-back relationship and their respective panels in edgeto-edgerelationship. I 7. Seam lock for securing together a plurality of panelsas defined in claim 4, wherein the juncture of said outer flange withsaid web is radiused, the radii having been selected such thatrefraction and diffusion of light passing through said panel in thevicinity of said channel member is minimized.

8. Seam lock for securing together a plurality of panels as defined inclaim 2, wherein said locking means is made of plastic. 7

v 9. Seam lock for securing together a plurality of panels as defined inclaim 2, wherein said first means are clear acrylic, said second meansis white acrylic, and said panels are plexiglas.

10. Seam lock for securing together a plurality of panels as defined inclaim 7 wherein the inner radius at said juncture is approximately twicethe outer radius at said juncture.

ll. Seam lock for securing together a plurality 'of panels as defined inclaim 6 wherein the combined length of a pair of adjacent inner flangesis less than the width of said outer wall whereby substantial clearanceis provided at the ends of said outer flanges in said recesses.

l2. Seam lock for securing together a plurality of panels as defined inclaim 2 wherein, said first means is cemented to its respective panel.

2. A seam lock for securing together a plurality of translucent panelsarranged in edge-to-edge abutting relationship to form a sign face foran internally illuminated sign, comprising locking means on adjacentmarginal edges of said panels for releasably locking adjacent panelstogether, said locking means comprising a material capable of passinglight therethrough and constructed to minimize refraction and diffusionof light passing through said panels in the vicinity of said lockingmeans to preclude shadows and discoloration and the like in said signface.
 3. A seam lock for securing together a plurality of panels asdefined in claim 2, wherein said locking means is made of a translucentmaterial and comprises channel members having preselected corner radiisuch as to minimize refraction and diffusion of light passingtherethrough.
 4. Seam lock for securing together a plurality of panelsas defined in claim 2 wherein said locking means comprises first lockingmeans carried by adjacent marginal edges of the panels and secondlocking means simultaneously interengaging and interlocking with saidfirst locking means to releasably hold the panels in said edge-to-edgerelationship, said first locking means comprising a web portion and anouter flange extending at substantially right angles from an edge ofsaid web portion, the outer surface of said flange being affixed to theback of a panel adjacent a marginal edge thereof with the webs ofadjacent locking means extending substantially perpendicularly and inback-to-back relationship from the back of adjacent panels, said secondlocking means interengaging and interlocking with said web portions. 5.Seam lock for securing together a plurality of panels as defined inclaim 4 wherein said first locking means is generally U-shaped with aninner flange extending substantially perpendicularly from the oppositeedge of said web, said inner flange being interengaged and interlockedwith said second locking means.
 6. Seam lock for securing together aplurality of panels as defined in claim 5, wherein said second lockingmeans comprises a generally C-shaped locking channel member having anouter wall and two depending sidewalls extending substantiallyperpendicularly from opposite edges of said outer wall, each of saidsidewalls having an inwardly directed flange means extending parallel tosaid outer wall and terminating short of each other, defining inwardlyfacing recesses, each of said recesses slidably receiving an outerflange of two adjacent generally U-shaped locking members therebyreleasably holding said U-shaped locking member sin back-to-backrelationship and their respective panels in edge-to-edge relationship.7. Seam lock for securing together a plurality of panels as defined inclaim 4, wherein the juncture of said outer flange with said web isradiused, the radii having been selected such that refraction anddiffusion of light passing through said panel in the vicinity of saidchannel member is minimized.
 8. Seam lock for securing together aplurality of panels as defined in claim 2, wherein said locking means ismade of plastic.
 9. Seam lock for securing together a plurality ofpanels as defined in claim 2, wherein said first means are clearacrylic, said second means is white acrylic, and said panels areplexiglas.
 10. Seam lock for securing together a plurality of panels asdefined in claim 7 wherein the inner radius at said juncture isapproximately twice the outer radius at said juncture.
 11. Seam lock forsecuring together a plurality of panels as defined in claim 6 whereinthe combined length of a pair of adjacent inner flanges is less than thewidth of said outer wall whereby substantial clearance is provided atthe ends of said outer flanges in said recesses.
 12. Seam lock forsecuring together a plurality of panels as defined in claim 2 wherein,said first means is cemented to its respective panel.